Seal apparatus

ABSTRACT

The sealing apparatus comprises (a) a heat seal jaw, (b) a heat seal bar having two heaters arranged in parallel, being provided in a front edge of said heat seal jaw and having a working surface, (c) a counter jaw disposed oppositely to the heat seal jaw, (d) a counter rail provided to said counter jaw and having the working surface, (e) a drive means for advancing/retracting the heat seal jaw and counter jaw relatively, (f) a heating means for actuating the heaters while clamping a packaging material by the working surface of the heat seal bar and the working of the counter rail and, (g) a cutter section comprising of a cutter disposed at the position between the two heaters and a resilient counter cutter, and is characterized in that the counter cutter is held by a holding section provided on the working surface of the heat seal bar or the counter rail and projecting from the holding working surface. The seal apparatus can improve hygiene and the flap formation of the packaging container.

TECHNICAL FIELD

This invention relates to seal apparatus.

BACKGROUND ART

In conventional manufacture of packaging container filling liquid foodsuch as milk, soft drinks and like, web-like packaging materialscomprising flexible laminate material are in-fed to a filling machine.In the filling machine, the packaging material is sealed along thelongitudinal direction, and is formed as tube like shape. While thetube-shaped packaging material is transported downward continually,liquid food is filled up upward. The tube-shaped packaging material istransferred to a seal apparatus, and is transversal-sealed in predefinedinterval While being clamped by the seal units from both sides, in theseal apparatus. By cutting the transversal-sealed portion, then aplurality of preliminary containers filled up predefined amount ofliquid food are formed, and the preliminary container is formed into afinal packaging container. The seal units face each other and have acounter jaw and a heat seal jaw disposed with freely forward/backwardmoving. The counter rail and the heat seal bar are disposed to thecounter jaw and the heat seal jaw, respectively.

FIG. 3 is a sketch drawing of a seal apparatus for transverse sealingthe packaging material filled up with contents liquid.

FIG. 5 is an illustration of a cutter counter section according aconventional seal unit.

FIG. 6 is a perspective view showing flap holdings of the containerfilled up with contents liquid.

In the views, the reference numeral 28 indicates the counter rail, thereference numeral 29 indicate the heat seal bar.

The web-shaped packaging materials 10 in two sheets are clamped betweena working surface of the counter rail 28 and a working surface of theheat seal bar 29.

In the working face facing against the counter rail 28 in the heat sealbar 2,9, the first, the second induction heaters 31, 32, having thepredefined intervals up and down, facing the packaging material 10 andhaving convex projection 77 are disposed.

In this case, the packaging material 10 is clamped with the counter rail28 and the heat seal bar 29 and is sealed transversally with pushing andheating by advancing forward the packaging material 10 each other.

The packaging material 10 has a laminate structure comprising of apolyethylene layer, an aluminum foil layer, an adhesive layer, a papersubstrate and a polyethylene layer in order to outside from inside ofthe formed packaging container.

Therefore, the packaging materials 10 in two sheets are clamped with thecounter rail 28 and the heat seal bar 29, and is heated by impressingseal voltage to the first, the second induction heaters 31, 32 withconvex projections 77.

The innermost polyethylene layer in the first portion 10 a and theinnermost polyethylene layer in the second portion 10 b of the packagingmaterial 10 are pushed and melted each other mainly in an areacorresponding to the first, the second induction heaters 31, 32.

Impressing of the seal voltage to the first, the second inductionheaters 31, 32 is stopped and the corresponding portion of the first,the second induction heaters 31, 32 are cooled.

A seal portion S comprising of the first, the second transverse sealingportion S1, S2 are formed in the portion corresponding to the first, thesecond induction heaters 31, 32 in the first portion 10 a and the secondportion 10 b.

Subsequently, the seal section S is cut with a cutter section 50, and acontainer is formed.

In the cutter section, a groove 55 is formed on the working surface ofthe heat seal bar 29 in order to prevent any deterioration of the cutter51 when the cutter 51 built-in to the counter rail 28 cuts the packagingmaterial 10 (10 a and 10 b).

In the conventional seal apparatus, the groove 55 is formed on theworking surface of the heat seal bar 29 and/or the heat sea jaw so asnot to damage the point of the cutter 51 when the cutter in the countersection cuts the packaging material 10 (10 a and 10 b). Therefore,however, when the packaging materials 10 are pushed by the workingsurface of the counter rail 28 and the working of the heat seal bar 29for the transverse sealing, because of no back pressure of the portionof the packaging material 10 corresponding to the groove 55, thecontents liquid remains as stagnant liquid 59 between the packagingmaterials 10 a and 10 b corresponding to cutter recess portion 55.

Therefore, the liquid of the stagnant liquid might unsanitarilydecompose before consumer's use because the stagnant liquid 59 remainsat the section S of the packaging material separated individually.

Moreover, when flap 71 adheres to the container wall in the formation ofthe container as shown in FIG. 6, an adhesiveness of the flap decreasein case the liquid of the stagnant liquid pollutes the adhesive area.

DISCLOSURE OF THE INVENTION

This invention solves problems of the conventional seal apparatus, andaims to provide with the seal apparatus that can improve hygiene andcontainer formation of the packaging container.

In the seal apparatus of this invention to solve a problem, the sealingapparatus comprises (a) a heat seal jaw, (b) a heat seal bar having twoheaters arranged in parallel, being provided in a front edge of saidheat seal jaw and having a working surface, (c) a counter jaw disposedoppositely to the heat seal jaw, (d) a counter rail provided to saidcounter jaw and having the working surface, (e) a drive means foradvancing/retracting the heat seal jaw and counter jaw relatively, (f) aheating means for actuating the heaters while clamping a packagingmaterial by the working surface of the heat seal bar and the working ofthe counter rail and, (g) a cutter section comprising of a cutterdisposed at the position between the two heaters and a resilient countercutter, and Is characterized in that the counter cutter is held by aholding section provided on the working surface of the heat seal bar orthe counter rail and projecting from the holding working surface.

In the preferable embodiment of the invention, the counter cutter ismounted by fitting with the holding section.

In the preferable embodiment of the invention, the counter cutterprojects from the working surface with a sectional chevron shape.

In the preferable embodiment of the invention, the counter cutterprojects from the working surface with a sectional rectangle shape.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is an explanatory drawing of the cutter part in accordance withthe seal apparatus in an embodiment of this invention.

FIG. 2 is a detailed section view of the cutter counter in theembodiment of this invention.

FIG. 3 is a schematic illustration of a seal apparatus for transversesealing the packaging material filled up with contents liquid.

FIG. 4 is an explanatory drawing of the container formed by transversesealing after filling up the contents liquid into thelongitudinal-sealed packaging material.

FIG. 5 is an illustration of a cutter counter section according aconventional seal unit.

FIG. 6 is a perspective view showing flap folding of the containerfilled up with contents liquid.

FIG. 7 is a sectional view showing the cutting function of the cuttersection according to another embodiment of this invention.

FIG. 8 is a sectional view of a cutter counter according to otherembodiment of this invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Modes of this invention are described in detail as follows, referring todrawing. In FIGS. 1, 2, 3 and 4, the tube-shaped packaging material 10comprising flexible laminated material is formed by curving theweb-shaped packaging material 11, 12 and sealing both edges inlongitudinal direction.

The packaging material 10 is carried underneath continually to the sealapparatus, in the seal apparatus, and is clamped by two seal units 14,15 in the predetermined interval, and a seal portion S is formed by atransverse sealing. In the meantime, liquid food 12 is filled up upwardin the packaging material 10. Both seal units 14, 15 have the counterjaw 14 a, 15 a and the heat seal jaw 14 b, 15 b. Counter jaws 14 a, 15 ais oppositely disposed to heat seal jaws 14 b, 15 b.

In the counter rail 28 installed on the front edge of the counter jaw 14a, 15 a and the heat seal bar 29 installed on the front edge of thecounter jaw 14 b, 15 b, a cylinder (not shown) as a drive means whichrelatively advancing. and retreating (right and left direction in FIG.3) the heat seal jaws 14 b, 15 b and counter jaws 14 a, 15 a is mounted.

A pair of forming flaps 21 a, 21 b supported with freely rocking by thecounter jaws 14 a, 15 a and the heat seal jaw 14 b and guiding thepackaging material 10, and forms the packaging material 10 intorectangular-shape.

As shown in FIG. 3, the seal unit 14 clamps the packaging material 10from both sides by advancing the counter jaw 14 a and the heat seal jaw14 b to the packaging material 10 from a seal starting position.

The seal unit 14 moves downward with clamping the packaging material 10,the heat seal bar 19 and the counter rail 18 strongly pressures the sealportion S, heat seal bar 19 heat generates heat in an aluminum foillayer of packaging material 10 by induction heating, and the packagingmaterial 10 is transverse sealed.

The sealing by the seal unit 14 is finished when the seal unit 15 movesto the seal starting position, and the counter jaw 15 a and the heatseal jaw 15 b begins to start ahead.

In this way, after sealing and cutting the packaging material 10 in themiddle of each seal portion S with the cutter of the cutter section apreliminary container is formed.

A preliminary container is finally formed a desired container bytransferring to a forming section (not shown in the figures), forming tothe predetermined shape, and being adhered flaps to top and bottom ofthe container.

The seal method by the seal units 14, 15 are described hereinafter. InFIG. 1, the packaging materials 10 in two sheets between the workingsurface of the counter rail 28 and the working surface of the heat sealbar 29 are clamped and is transverse-sealed.

In facing face against the counter rail 28 in the heat seal bar 29, thefirst, the second induction heaters 31, 32 are disposed, havingpredefined intervals up and down, facing the packaging material 10 andhaving convex projection 77. The first, the second induction heaters 31,32 have tube-shape capable of passing cooling water in the heaters.

The packaging material 10 has a laminate structure comprising of apolyethylene layer an aluminum foil layer, an adhesive layer, a papersubstrate and a polyethylene layer in order to outside from inside ofthe formed packaging container.

The packaging material 10 is clamped with the counter rail 28 and theheat seal bar 29 and is sealed transversally by advancing forward thepackaging material 10 each other.

The packaging materials 10 in two sheets are clamped with the counterrail 28 and the heat seal bar 29, and is heated by impressing sealvoltage to the first, the second induction heaters 31, 32 with convexprojections 77 through a controller (not shown in figures) of theheating section.

The innermost polyethylene layer in the first portion 10 a and theinnermost polyethylene layer in the second portion 10 b of the packagingmaterial 10 are pushed and melted each other mainly in areacorresponding to the first, the second induction heaters 31, 32.

Impressing of the seal voltage to the first, the second inductionheaters 31, 32 is stopped and the corresponding portion of the first,the second induction heaters 31, 32 are cooled.

A seal portion S comprising of the first, the second transverse sealingportion S1, S2 are formed in the portion corresponding to the first, thesecond induction heaters 31, 32 in the first portion 10 a and the secondportion 10 b.

The seal section S is cut with a cutter section 50, and each containeris formed. The cutter section comprises the cutter 51 built-in tocounter rail 28 and the counter cutter 53 built-in to heat seal bar 29.

The counter cutter is formed with elastic material such as soft rubber,hard rubber, a synthetic resin, synthesis flexible material, natureflexible material and is mounted by a holding part to hold the countercutter.

According to the invention, the counter cutter is held holding sectionprovided on the surface of the heat seal bar or counter rail. In theembodiment, the counter cutter projects from the working surface of theheat seal bar 29 with a sectional chevron shape.

When a cutter cuts packaging material 10 (10 a and 10 b), due topressure from the counter rail 28 and the heat seal bar 29 fortransverse sealing to packaging material 10 and due to back pressure ofelasticity of the counter cutter corresponding to packaging material 10of cutter section 55, the contents liquid is squeezed out and stagnantliquid is not generated between packaging material 10 a and 10 b near tothe counter cutter 53.

In addition, the counter cutter can control abrasive wear, damage of thepoint of cutter 51 as much as possible because the shock can be kept inminimum due to the resiliency cushioning material when the point ofcutter 51 hits the resiliency cushioning material in the step of cuttingthe packaging material 10 (10 a and 10 b) by cutter 51 mounted by theholding part to hold counter cutter. Therefore, a lifetime of the cuttercan be protected for long time.

With FIG. 2, moreover, the counter cutter is described in detail. FIG. 2(A) shows a condition of the counter cutter before the packagingmaterial 10 is pressed by the counter rail 28 and the heat seal bar 29.FIG. 2 (B) shows a condition of the counter cutter when the packagingmaterial 10 is pressed down by the counter rail 28 and the heat seal bar29 for the transverse sealing.

In the figures, R1, R2 are the length that each counter cutter projectsfrom holding section. As shown the following, elastic repulsive force Pequivalent to displacement length of R1-R2 is generated.P=E×S (R 1−R 2)/Q

-   E: Elastic modulus-   S: Cross section of a displacement section of a counter cutter

Moreover, according to other embodiment of invention, as shown in FIG.2, a K1 part of the holding part of the cutter counter becomes smallerthan K2 part, and the cutter counter is held along fitting.

Because the counter cutter is easily exchanged if necessary, labor andtime for exchange can be minimized.

In addition, this invention is not limited to the above-mentionedembodiment, potentially various modification based on the spirit of thisinvention will be not excluded from the scope of this invention.

As shown in FIG. 7, for example, the working surface of the heat sealbar 29 may be flat for the heat seal bar without the projection.

As shown in FIG. 7, the point of the cutter 51 is protected from thewear damage because the shock can be kept in low-level by deformation ofthe elastic counter cutter after the cutter 51 cuts the packagingmaterial 10 (10 a and 10 b).

The method of heat seal may include supersonic wave heating andresistance heating as well as induction heating.

The sectional shape includes, as shown in FIG. 8 (A), the embodimentthat the counter cutter projects from the working surface with asectional rectangle shape and as shown in FIG. 8 (B), the embodimentthat the counter cutter projects from the working surface with asectional rectangle shape and inclined surfaces.

As above-mentioned, the packaging material is hygienic because thestagnant liquid does not stay in the seal portion.

Scattering and container wall pollution of the contents from thestagnant liquid are prevented at the timing of cutting, and thecontainer can be formed well. Moreover, with the counter cutter ofelastic material, a life-time of the cutter can be protected for alongtime.

A counter cutter is held by fitting in the holding section.

Therefore, everyone can desorbs with the counter cutter easily.

A holding part arranged in a working surface of counter rail as anembodiment which is reverse to the above-mentioned embodiment can hold acounter cutter.

INDUSTRIAL APPLICABILITY

The seal apparatus of this invention are used to a machine packaging andfilling a container packing liquid food, such as cow milk, soft drinkand like.

1. A sealing apparatus comprising (a) a heat seal jaw, (b) a heat sealbar having two heaters arranged in parallel, being provided in a frontedge of said heat seal jaw and having a working surface, (c) a counterjaw disposed oppositely to the heat seal jaw, (d) a counter railprovided to said counter jaw and having the working surface, (e) a drivemeans for advancing/retracting the heat seal jaw and counter jawrelatively, (f) a heating means for actuating the heaters while clampinga packaging material by the working surface of the heat seal bar and theworking of the counter rail and, (g) a cutter section comprising of acutter disposed at the position between the two heaters and a resilientcounter cutter, characterized in that the counter cutter is held by aholding section provided on the working surface of the heat seal bar orthe counter rail and projecting from the holding working surface.
 2. Aseal apparatus as defined in claim 1, wherein the counter cutter ismounted by fitting with the holding section.
 3. A seal apparatus asdefined in claim 1, wherein the counter cutter projects from the workingsurface with a sectional chevron shape.
 4. A seal apparatus as definedin claim 1, wherein the counter cutter projects from the working surfacewith a sectional rectangle shape.